Autonomous Boat
Overview The goal of this project is to create an autonomous, sulf-sufficient sailboat. The boat will harness wind energy to propel itself through the water, and solar energy to power its electronic systems. An onboard processor will serve as the boat's navigator and captain, controlling the other onboard components. Components The boat will consist of a number of key components: *Hull *Sail *Rudder *Wind Vane *Processor *Solar Panel *Battery Hull The hull is currently being protoyped using a plastic bottle with a section in its side removed. While this floats and is waterproof we hope to replace it with a mor epurpose-built hull which will be more seaworthy. Repalcement candidates include: *Pre-made wooden model sailboat *Pre-made plastic toy sailboat *Custom boat carved from styrofoam block Sail Current designs do not call for a very sophisticated sail. The sail and mast will likely be a signle joined piece with the sail incapable of being furled. The sail does not need to be flexible and may simply be a rigid piece aluminum for instance. The mast will be a long rod affixed to a servo motor at its base with the sail affixed to its top. The servo motor will turn the mast to position the sail at the proper angle to catch the wind and propel the boat forward. This servo will be controlled by the onboard processor which will use input from the anemometer to determine the proper orientation of the sail. Rudder The rudder will be a flat, square-shaped, solid piece of metal, wood, or plastic which will be affixed below the waterline on the rear of the boat by a rod attached to a servo motor. The rudder will be capable of being turned roughly 45 degrees to either the left or right, which when the boat is in motion will act to rotate the boat, allowing it to change heading. The servo motor will be controlled by the onboard processor which will change its orientation to adjust the boat's heading. Wind Vane The wind vane will be used to determine the direction the wind is coming from in order to allow for the sail to be oriented properly. A wind vane will be affixed to a rotary optical encoder which will send an electrical signal to the processor informing it of the angle of the wind vane and thereby the direction of the wind. Processor Currently an Arduino Uno is planned as the boat's onboard processor. This microcontroller has digital pulse width modulation capable output pins which will be used to control the servo motors attached to the sail and rudder. It also has input pins capable of receiving input from the wind vane's optical encoder as well as any other sensors such as a compass. The Ardino also has the processing power to computer the necassary angles for the sail and rudder as well as a course for the boat to take. Solar Panel and Battery The electronics of the boat will be powered by solar energy obtained by te solar panel and stored by the battery. The battery is planned to be a 9v rechargable battery pack which will be capable of providing enough voltage to power the processor as well as the servos and sensors. The solar panel will have a built in converter to charge the 9v battery. Programming The processor controls 2 systems, the sail and the rudder. The orientation of the sail is simply a function wind direction because the boat always wants to go forward and the wind vane already takes into account the orientation of the baot. The orientation of the rudder is the result of the processor's navigation routine, which will have to take in input from all of its sensors, the compass in order to tell whether it is on course, the wind vane in order to tell whether it should tack in response to an unfavorable wind direction, and its own memory to know where it is trying to go.